The reason you aren't getting an answer is because you're asking about something that isn't mass produced. So every single build is going to be a contracted cos

The reason you aren't getting an answer is because you're asking about something that isn't mass produced. So every single build is going to be a contracted cost with many variables. Saying "I want a 65nm fab" doesn't mean anything. What type of EUV scanners do you want, how large of wafers do you want to handle, how many wafers at once, size of the clean room, etc. There is no answer, it's whatever you could get someone to do the job for + materials cost. We only have estimates for cutting edge facilities because we know what public companies have recently spent to produce those fabs. It's like asking "if I had $100m, how large of a secret underground meth production facility could I have built"....who knows, it's bespoke.